Fix exception handling line table problems introduced by r173593

r173593 made us a little too eager to associate all code at the end of a
function with the user-written 'return' line. This caused problems with
breakpoints as they'd be set in exception handling code preceeding the
actual non-exception return handling code, leading to the breakpoint never
being hit in non-exceptional execution.

This change restores the pre-r173593 exception handling line information where
the cleanup code is associated with the '}' not the return line.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@174206 91177308-0d34-0410-b5e6-96231b3b80d8
[analyzer] Reuse a LazyCompoundVal if its type matches the new region.

This allows us to keep from chaining LazyCompoundVals in cases like this:
  CGRect r = CGRectMake(0, 0, 640, 480);
  CGRect r2 = r;
  CGRect r3 = r2;

Previously we only made this optimization if the struct did not begin with
an aggregate member, to make sure that we weren't picking up an LCV for
the first field of the struct. But since LazyCompoundVals are typed, we can
make that inference directly by comparing types.

This is a pure optimization; the test changes are to guard against possible
future regressions.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@174211 91177308-0d34-0410-b5e6-96231b3b80d8
Re-apply "[analyzer] Model trivial copy/move ctors with an aggregate bind."

With the optimization in the previous commit, this should be safe again.

Originally applied in r173951, then reverted in r174069.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@174212 91177308-0d34-0410-b5e6-96231b3b80d8
[analyzer] Explain why we have system-header-simulator*.h files.

Suggested by Csaba. Text based on an e-mail of mine on cfe-dev.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@174213 91177308-0d34-0410-b5e6-96231b3b80d8